To monoblock or not to monoblock McIntosh MC275's

Effischer, thanks very much for the nice words, informative references, and good comments.  Interestingly, I took the "Weber's Law" test four times, using four different settings of the volume control on the computer.  On the low volume trials within each test my answers were MUCH better (averaging 85% correct) than on the high volume trials (averaging 30% correct).  So between the two conflicting references that are cited at the second link you provided, my results would indicate that the Weber's Law reference is the correct one.

Thanks again.  Best regards,
-- Al
 

Wondering if anyone has tried MC275’s in mono mode recently or general impressions of MC275’s in stereo mode?  Is the tube sound favorably compared to Primaluna 6 mono, 7 mono or evo series?

thanks

i've read the magazine 'stereo review' since the early 70's to their retirement. julian hersh said to increase volume by 3 decibals you need to triple your power. who is right here??

@g_nakamoto, for a given load impedance the ratio of two power levels is expressed in db by the following formula:

db = 10 x log(P1/P2)

where "log" is the base-10 logarithm.

From that it can be calculated that a 3 db increase corresponds to a doubling (not tripling) of power. Or more precisely, a doubling of power corresponds to an increase of 3.0103 db, which is usually rounded off to 3 db.

And a 3 db increase in the amount of power delivered to a speaker will result in a 3 db increase in the volume that is produced by that speaker, at a given distance, assuming that the speaker is not being driven so hard that "thermal compression" or other factors cause its behavior to become significantly non-linear.

Mr. Hirsch might also have referred at times to a commonly stated rule of thumb guideline that a **subjective** perception of "twice as loud" requires ten times as much power, which is an increase of 10 db.

I have no idea why or if he might have referred to a tripling of power.

Regards,
-- Al